With the development of multimedia technology and Internet, digital multimedia products can be issued via various channels, some may breach copyright protection.
An information concealing technology is used to convert individual information, for example, copyrights, trademarks or manufacturers, into a watermark, and the watermark is loaded and hidden into a multimedia file for verifying copies or tracking the source of illegal copies.
However, current watermarks are easily revised or removed, reducing security levels. An improved copyright information concealing method would be beneficial.